Effects of Docosahexaenoic Acid Supplementation During Pregnancy on Gestational Age and Size at Birth: Randomized, Double-Blind, Placebo-Controlled Trial in Mexico

BackgroundThe need for omega-3 fatty acids, especially docosahexaenoic acid (DHA), during pregnancy has received much attention, but evidence of effects on birth outcomes is limited.ObjectiveTo evaluate whether prenatal DHA supplementation increases gestational age and birth size.MethodsWe conducted a double-blind, randomized, placebo-controlled trial in Cuernavaca, Mexico. We randomly assigned 1,094 pregnant women (18 to 35 years of age; median DHA dietary intake, 55 mg/day) to 400 mg/day of algal DHA or placebo from 18 to 22 weeks of gestation through delivery. Birth outcomes (968 live births and 5 stillbirths) were ascertained from hospital records within 24 hours of delivery.ResultsIntention-to-treat analysis showed no differences between the control and DHA group (all p > .05) in mean gestational age (39.1 + 1.7 and 39.0 ± 1.9 weeks, respectively), weight (3.20 + 0.47 and 3.21 ± 0.45 kg, respectively), length (50.3 ± 2.7 and 50.3 ± 2.3 cm, respectively) and head circumference (34.3 ± 1.8 and 34.3 ± 1...